Positive dysphotopsia after intrascleral intraocular lens fixation: a case report

Abstract

Background: Positive dysphotopsia is a symptom caused by the reflection of incident light through the pupil at the inner surface of the intraocular lens (IOL) edge after cataract surgery and is perceived as an abnormal arcuate or radiating photopic image at night or indoors with a light source. Although positive dysphotopsia is one of the most important symptoms that affect patients after cataract surgery, it is still not well known even among ophthalmologists. Positive dysphotopsia as the cause of patient complaint following intraocular surgery other than cataract surgery has not been identified.

Case presentation: A 52-year-old man underwent IOL extraction and intrascleral IOL fixation for bilateral IOL subluxation at another hospital. The right eye had good subjective visibility, but the patient noticed symptoms of light sources appearing divided into multiple lights indoors after surgery in the left eye. Because the cause of the symptoms could not be identified, the patient visited our department. At the time of his first visit, the corrected visual acuity in both eyes was good, and ocular findings in eye position, motility, intraocular pressure, and fundus were within normal limits. The elongated holes of peripheral iridectomy (PI) created during previous intrascleral IOL fixation were observed to be approximately 2 mm in length on the nasal side in both eyes. The PI hole in the right eye was covered by the optics of the IOL, whereas the edge of the IOL overlapped the center of the PI hole in the left eye. Accordingly, we concluded that the abnormal photopic image in the left eye was caused by positive dysphotopsia, in which light passing through the PI hole was reflected by the edge of the IOL. We attempted surgical closure of the PI hole, resulting in the complete disappearance of positive dysphotopsia.

Conclusions: A PI hole created during intrascleral IOL fixation may cause postoperative positive dysphotopsia depending on the position of the IOL edge. Thus, surgeons should be aware of the importance of the size and location of the PI hole when creating it during surgery.

Keywords: Intraocular lens edge; Intrascleral intraocular lens fixation; Peripheral iridectomy; Positive dysphotopsia.

Fig. 1

Image graphics prepared by the patient according to his complaints. He explained that the light sources indoors were divided into multiple lights (red circle part) when viewed only by the left eye. The image depicted here is our own property

Fig. 2

Slit-lamp photomicrographs at the initial diagnosis in the right eye (a, c) and left eye (b, d). The PI holes with approximately the same size and position in both eyes were observed. In the retroillumination image, the right eye is covered by the IOL optics (c), whereas the IOL edge was observed in the center of the PI hole in the left eye (d)

Fig. 3

Anterior ocular segment optical coherence tomography findings. A slight tilt was observed in the left eye compared to the right eye. Under dark conditions, the IOL optical surface directly below the PI hole was observed in the right eye, whereas the PI hole overlapped the IOL edge in the left eye

Fig. 4

Video images during surgery. The center of the PI hole was pierced with a 10–0 polypropylene suture (a). The needle was pulled out of the eye using a 27-gauge needle (b). A corneal incision of approximately 1.5 mm wide was created directly above the PI hole (c). The 10–0 polypropylene suture was pulled out of the eye through the corneal incision from the anterior chamber (d). The suture was ligated out of the eye (e). The ligature was returned into the eye (f)

Fig. 5

Postoperative slit-lamp photomicrographs. The PI hole was closed, and the IOL edge is not observed in the retroillumination image